I'm running OpenELEC, and with the Confluence skin I can see the available storage for my /storage partition in Settings > Info > Storage. This is on the USB key used to boot the system, as all media is on a NAS. OpenELEC is a Linux system.

However in Fusion, the Storage section of the "Settings Home" screen simply shows:

"Unavailable
Unavailable
Unavailable
Unavailable
Unavailable"

and no numbers or figures, meaning the Storage section is somewhat unattractive.

In the Settings > Info > Storage panel for Fusion, there is a list of 6 mount points displayed, eg. "C: Unavailable", "D: Unavailable", "E: Unavailable" etc., all of them "Unavailable".

Is the Fusion skin "Windows" specific, and not taking Linux into account when accessing storage information?

This skin is still beta, which means that many features can be missing and
generally much work is to be done. This beta is only aimed at users
who want to test drive the skin and help the author to remove bugs and get all functions running as they should.

Please look in the bugs forum thread, if you find bugs report them there if they are not allready reported.

There is also a feature suggestion forum thread, here you can ask about improvements you think can be added to the skin.